Effects of Selective Serotonin Reuptake Inhibitors and Serotonin-Norepinephrine Reuptake Inhibitors on Toll-Like- Receptors Expression Profiles

Abstract

Toll-like receptors (TLR) signal activation and expressions have been associated with major depressive disorder (MDD). Changes of TLR expressions after antidepressants treatment were reported in our previous work. However, the effects of antidepressants on TLR expressions were limited to selective serotonin reuptake inhibitor (SSRI) and imipramine. This study aimed to investigate the differences of TLR expression profiles between patients treated with SSRI and those treated with serotonin-norepinephrine reuptake inhibitor (SNRI). 68 patients (15 males and 53 females) with MDD before and after treatment with SSRI or SNRI were recruited. HAMD-17 was used to assess the severity of MDD. The mRNA expression levels of interleukin (IL)-6 and TLR in peripheral blood mononuclear cells (PBMCs) were examined in parallel with a housekeeping gene, using real-time polymerase chain reaction (RT-PCR). IL-6 and TLR 2, 3, 4, 6, 8 and 9 mRNA expressions decreased after SSRI treatment. However, only TLR 2, 5 and 6 mRNA expressions decreased after SNRI treatment. These findings suggest that the SSRI and SNRI have different effects on changing TLR expression profiles.